Link for tractor rails



April 24, 1956 E. c. BAUER, JR

LINK FOR TRACTOR RAILS 2 Sheets-Sheet 1 Filed NOV. 3, 1952 April 4, 1956 E. c. BAUER, JR 2,743,140

LINK FOR TRACTOR RAILS Filed Nov. 5, 1952 2 SheetsSheet 2 l N VENTOR Eugene C. BOLLQP'JIZ.

ATT RNEY :nected to a similar 2,743,140 v LINKFOR TRACTOR RAILS "Eugene C. Bauer, .llr 'Park Ridg'efllli, assignor to Kensington, Steel Company, Chicago, 11]., a corporafiou of Illinois 1 Application November 3, 1952,.Serial Na. 318,498 4 Claims. to]. ops- This invention relatesito tractor rails of the endless type used on earth moving equipment and the like, and more particularly, to a complete .oneepieee link unit of .austenit-ic manganese steel which may be..readily conadjacent unit to form the track or rail. 1 j 1 Heretofore, it has been the general-practice tornake .the units of the rail in a number of separate parts. For example, it has been customary separately to forge the two, :side members or links of the unit hom -suitable steel and :then connect these .units by a separate hollow steel bushing whose endspare press fitted gintothe counterbore of anoverlapping link, said bushing'inturnreceiviug Moreover,

a pin for connecting one unit with another. the opposite edge portions are required towbe machined to provide asmooth surface for attaching :the shoes or ;,.g-rouser plates and also for hardness penetration. Aside from the multiplicity of parts requiring time and labor .for

unachining and assembling units of the type just described have, by comparison with :austenitic manganese steel,

short useful field life. 1

Therefore, an objectof the inventionis to provide a .tone-piece-link unit made ofsaustenitic manganese :steel and thereby provide a link of greater longevity under adiflicult conditions of use, the same beingmade by casting procedures. That is to say, the'present invention contemplates the provision .of a link wherein the side members and the sprocket engaging pin-receiving :barrel are cast in oneintegral piece, together with a grouser plate supporting web --locatedinwardly of the eyes of the side members.- Austenitic manganese steel is not generally machinable, and therefore, the rail and shoe surfaces are made true and smooth during casting, and, after the integrated structure has been completed, the internal, "bores of the eyes and the barrel'may be rendered smooth to the. desired degree by appropriate finishing procedures.

A further object of the invention 'is'to provide :a unit of the type set forth which requires less time to assemble in track "form because it can be setup in the shop to .greater advantage and more importantlyless time to I consists in the structure and procedures hereinafter more fully set forth and claimed.

A preferred embodiment of the invention is shown in the accompanying drawings,in which:

Figure 1 is a diagrammatic perspective view illustrating a track including. the present units about to be connected in final endless form.

grouser plates in perspecthe regular Figure 7 is a side elevation of one of the units'shown :in Figures 1-6.. V

Figure 8 is a partial top .plan view of the unit .shown inFigure7.

Figure 9 is a vertical cross-sectional viewtakenmon the Similar reference characters designate corresponding parts throughout the several figuresof thedrawings.

As' will be observed from Figure 1, .the track or rail designated generally :as T, comprises a plura'litylof cast track units .A which are connected in track formation by steel .pins B while the end units of the completed track are joined by a master steel connecting pin B. Each unit A is provided with a grouser .plate C- which is fitted to one face of the unit to provide adequate earth engaging traction. I

Referring to the unit A, it will be observed thatthe same includes an integral. one-'piece zbody which may .be generally described as being narrow .at one closed end and wide and open at the opposite end, resulting in .a bifurcated formation. Said bodyfis formed with-opposite side members-1 which are of .a substantially skeleton formation inthe respect that they are provided with an opening divided by a vertical strut and otherwise divided by a roller load sustaining portion and a grouser plate portion as will be seen from the drawings and laterappear more in detail: The narrow ends of the members 1 are integrally connected by a'tubular sprocket engaging and pin receiving barrel 2 arranged between the sidemembers with the bore thereof opening through the eyes 2a-of said side members. The opposite .end 3 of the body 'is provided with laterally spaced eyes 311. Thespacing of said eyes is such asto receive the narrow end of the adjacent unit including the barrel 2 so that when the units are assembled in series the barrel 2 of one unit will become alined with the eyes 3a ofthe adjacent unit to receive the rail assembly pins 3 which are fitted into eyes 2a, 3a,

. by a press .of large tonnagerating. 011 the other hand,

. the master pin B is driven in place in the field to'c'onnect the end links of the otherwise assembled rail about the tractor'sprockets and rollers. l

The side members 1 are integrally connected inwardly of the eyes 3a by a transverse web or tie bar '4 which guards against spreading of the unit, at the wide endand provides additional supporting area for the grouser plate. This web is located inwardly of the eyes 3:: so that the barrel 2 of the mating link'can turn freely relative thereto. Each side member '1 has its outer face recessed adjacent the eyes 2a and also has its inner face recessed H between the eyes 3a to accommodate the relatively telescoping parts of a related link and also includes the opposite grouser plate attaching portion 5 and the roller load supporting beam 6 which is wider and thicker at the location of strut 10 than the grouser plate portion 5 as will be apparent from Figs. 3 and 9, and whose outer ment.

by the-vertical strut 10 to provide cantilever strength i and stability to the beam portions 6 of the side members under heavy load and tractive effort.

After the casting has been made, the bore of barrel 2 andeyes 2a as well as the bores-f the eyes 3a preferably have their internal surfaces pre-stressed or work hardened by suitable finishing procedures due to the fact that austenitic manganese steel is commercially notmachineable in regard to finishing bores of eyes 2a and 3a. 7

Referring first to the bore 2, the same is made initially by a washed sand core comprising 20% zircon by volume to minimize shrinkage. The original bore diameter is less than the final diameter resulting from such work hardening operations as may be desirable. For example, the result of work hardening the internal diameter of the barrel elevates the initial Brinell of approximately 230 to within the range of 350-375. i

The internal bores of the eyesSa are made with cores also including 20% zircon and are finished to the extent that they will firmly engage or grip the opposite ends of the related pin B to insure a press fit.

The pin B, Figure 5, is of uniform diameter and is press fitted in the eyes 3a which are of a lesser diameter than the diameter of the pins B thereby locking said pins solidly in the eyes 3 for holding the links A together.

The master connecting pins B, Figure 6, are provided with a head having longitudinal serrations at one end as indicated by B so that when this pin is driven in place in the field to complete the endless track, the adjacent units will be firmly connected with less effort than the pressure required to set pins B in the shop where presses are available. That is to say, the shank or body of the master connecting pin B has lesser diameter than the pins B to be more readily initially insertable with field equip- ,ment, and the knurled head portion, whose overall diameter is greater than the diameter of the shank, will penetrate into the metal of the bore in one of the eyes to securely and firmly lock the master pin in position with the maximum pressure available from the field equip- The serrations being longitudinal facilitate seating of the master pin but since they become embedded in the related eye, the anchorage is firm and secure.

. When the units A are assembled in track formation, the pins B are inserted in the shop through the alined bores of the eyes and the barrel by the aid of a hydraulic press. Equivalent apparatus or tools may be used in the field to insert the pin B.

I claim: 1. A link unit for connection with similar units to constitute a tractor rail, said unit being a one-piece body cast of alloyed austenitic manganese steel, and comprising opposite side members formed within their end portions with registering pairs of pin receiving eyes and also probetween eyesin the same longitudinal plane an arched roller load sustaining beam cantilevered to a medial vertical strut extending between the medial portion of the arch and the grouser plate attaching portion, a pin receiving barrel having a bore axially aligned with the axes of a related pair of opposite eyes at one end of the side members, and a tie bar transversely connecting the grouser plate attaching portions of the side members between the strut and theeyes opposite the eyes aligned with the barrel to prevent spreading of theside members and provide further support for the grouser plate.

2. A tractor rail including, in combination, a plurality of integral individual link units each comprising, a onepiece cast steel body, each unit having opposite side members formed with an opening in its side wall and provided at their ends with registering pin receiving eyes, a vertical strut located medially of said opening, an inner roller load supporting cantilever type beam portion and an outer grouser plate attaching portion for each side member,vthesaid beam portion having greater vertical and lateral thickness than the grouser plate attaching portion at the location of said strut for supporting the roller load imposed on said beam portion, a tubular sprocket engaging pin receiving barrel integrally connected with the sidemembers and axially aligned with a related pair of eyes in the opposite side members, a transverse tie bar connecting the side members in the general plane of the grouser plate attaching portions to hold the side members against spreading at a point in the unit longitudinally spaced from the barrel and also provide asupport for the grouser plate, and shop assembly pins of greater diameter than the eyes press fitted into the registering eyes of the side members.

3. A tractor rail according to claim 2, wherein the unconnected end links of the linearly assembled rail are secured together in the field by a field driven master pin,

said pin having a body of less diameter than the shop assembly pins and a driving fit with respect to related registering eyes and the barrel, and a head portion for the pin provided with longitudinally disposed serrations of larger diameter than the body of the pin and of a length to-firmly engage in one of the said registering eyes.

4. A tractor rail according to claim 2, wherein each grouser plate attaching portion is provided at each side of the vertical strut with openings for receiving fastenings to connect a grouser plate with its related link.

References Cited in the file of this patent UNITED STATES PATENTS 12,667,386 Mathison Jan. 26, 1954 

